Science or magic? Polymers and pencils

We kicked off Science Week with a demonstration of the power of polymers.

We took a plastic bag filled with water and a bunch of sharpened pencils into the playground and predicted what would happen if the pencils were pushed through the bag.

We found that even if you pushed the pencil right through, the water stayed inside!

This is because plastic is a polymer, which means that it is made of long chains of the same particles. When you pierce the bag it breaks the chain but the end particles are sticky and make a seal around the pencils.

It’s a different matter when you take the pencils out!

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